of: Move of_dma_configure() to device.c to help re-use

Move of_dma_configure() to device.c so it can be re-used for PCI devices to
obtain DMA configuration from DT.  Also add a second argument so that for
PCI, the DT node of root bus host bridge can be used to obtain the DMA
configuration for the slave PCI device.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> (AMD Seattle)
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Rob Herring <robh+dt@kernel.org>
CC: Joerg Roedel <joro@8bytes.org>
CC: Grant Likely <grant.likely@linaro.org>
CC: Russell King <linux@arm.linux.org.uk>
CC: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Murali Karicheri
2015-03-03 12:52:09 -05:00
committed by Bjorn Helgaas
parent ed74862103
commit 1f5c69aa51
3 changed files with 64 additions and 56 deletions

View File

@@ -2,6 +2,9 @@
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/of_iommu.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
@@ -66,6 +69,62 @@ int of_device_add(struct platform_device *ofdev)
return device_add(&ofdev->dev);
}
/**
* of_dma_configure - Setup DMA configuration
* @dev: Device to apply DMA configuration
* @np: Pointer to OF node having DMA configuration
*
* Try to get devices's DMA configuration from DT and update it
* accordingly.
*
* If platform code needs to use its own special DMA configuration, it
* can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
* to fix up DMA configuration.
*/
void of_dma_configure(struct device *dev, struct device_node *np)
{
u64 dma_addr, paddr, size;
int ret;
bool coherent;
unsigned long offset;
struct iommu_ops *iommu;
/*
* Set default dma-mask to 32 bit. Drivers are expected to setup
* the correct supported dma_mask.
*/
dev->coherent_dma_mask = DMA_BIT_MASK(32);
/*
* Set it to coherent_dma_mask by default if the architecture
* code has not set it.
*/
if (!dev->dma_mask)
dev->dma_mask = &dev->coherent_dma_mask;
ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
if (ret < 0) {
dma_addr = offset = 0;
size = dev->coherent_dma_mask;
} else {
offset = PFN_DOWN(paddr - dma_addr);
dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
}
dev->dma_pfn_offset = offset;
coherent = of_dma_is_coherent(np);
dev_dbg(dev, "device is%sdma coherent\n",
coherent ? " " : " not ");
iommu = of_iommu_configure(dev, np);
dev_dbg(dev, "device is%sbehind an iommu\n",
iommu ? " " : " not ");
arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
}
EXPORT_SYMBOL_GPL(of_dma_configure);
int of_device_register(struct platform_device *pdev)
{
device_initialize(&pdev->dev);